Document serialisation used by Cardano

[coot]

To know the wire format it's not enough to know how network messages or ledger data structures are encoded but one also needs to know how HFC encodes them across different eras. Network & ledger provide CDDL specs for that and it would be nice to provide overview how these CDDL specs integrate via HFC, specifically how HFC encodes:

• transactions ids
• transactions
• block headers
• blocks

There are also things that are not affected by HFC and it would be nice to have a list of these too (e.g. slots & points, tip(?) (I mean Tip blk), maybe something else as well).

[ghost]

Do I understand correctly this means providing proper CDDL files and accompanying documentation for HFC data structures?

[coot]

That's up to the consensus to decide if they want to maintain CDDL specs - so I'll let @dnadales decide, but at least document the serialisation format for things that affected and compile a list of things that are not affected.